Remote Switch - Digital Equipment COLORWRITER LSR 2000 Service Manual

Colorwriter LSR 2000 Printer
Service Guide
3: Operation
+24VDC consists of:
• Normal +24VA, which is shut off when SW2 is turned off by
opening the front door, the fixing unit cover, or the pick-up
cover; and
• +24VB, which is always on whether SW2 is turned on or off.
• +24VC, which is shut off in the power-saving mode or when the
cover is opened, is generated in the mechanical controller PCB.
The 5V power supplied to the video controller is monitored using
the 5VB signal fed back from the terminal PCB to ensure it always
will be supplied.
This printer enters the power-saving mode when receiving the
Note:
command from the video controller. It returns to the normal mode
when a command is received from the video controller to cancel the
power-saving mode.

Remote switch

When the power switch on the printer is turned OFF, the power
supply circuit sets the power off signal (POFF) sent to the DC
controller to "H." When the printer is ready to be turned off, the
DC controller sets the power off control signal (PCONT) to "L."
This stops the switching regulator for the power supply circuit and
turns off the printer.
Protection function
The power supply circuits for +24VDC and +5VDC have an
overcurrent/overvoltage detection function which is activated if
some problem has occurred. If this function is activated, it
automatically shuts off the output voltage to protect the power
supply circuit. If no DC voltage is output from the power supply
circuit because the overcurrent protection function has been
activated, turn OFF the power switch (SW1), disconnect the power
cable, rectify the problem with the loads, and then turn the power
switch on again. Do not turn on the printer for about two minutes
after turning it off.
If overcurrent flows in the AC line, the circuit breaker on the circuit
is turned off to shut off the output voltage.
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